Each year has 6 levels to it, and there are 11 bonus levels on top of that- 10 "gold brick" levels and one final bonus level for a character token (Voldemort).

(I've completed all 4 years and am now in free play to unlock characters and earn remaining gold bricks.

(it works like finding a red brick and then being able to buy the extra) which is only a problem if your a completionist like me

Outside of these levels, you get to roam around Hogwarts where there are plenty of hidden character tokens, gold bricks, red bricks, and students in peril

Collecting all the gold bricks, red bricks, character tokens, house crests, students in peril, and true wizard levels was a blast and I found this to be my all time favorite of all the Lego games so far.